My invention relates to radiology, and in particular, to arrangements for generating x-ray microbeams.
Most familiar radiology systems operate with "flood" x-rays, that is, x-rays which are diffuse. An x-ray microbeam by comparison, is narrow and sharply formed; the x-ray image is confined to a small area. The essential advantage of an x-ray microbeam system is that successive areas of exposure may be determined interactively, for example, by computer.
X-ray microbeam generators have been developed in which an x-ray emissive target is scanned with a computer controlled electron beam. X-rays from the target are formed into a microbeam. The microbeam, which scans in accordance with the electron beam, is directed through an irradiation field. For radiography, an array of detectors is used to intercept x-rays attenuated by an object in the examination field. Radiopacity signals from the detector array are processed to yield radiographic information.
Prior generators produce a continuous x-ray microbeam, however, which may degrade radiographic information due to scattering and boundary effects at the detector. Further, continuous microbeam systems may not satisfy positional accuracy and reproducibility requirements in certain applications, such as, speech research and integrated circuit mask fabrication. It is therefore an object of the invention to provide an improved arrangement for developing precisely directed x-ray microbeams.